1. Field of the Invention
The present invention generally relates to a water heating device, and in particular to a water heating device for heating water running along pipelines from a water supply to a faucet located below the water supply by first converting mechanical energy of the running water into electricity that is then employed to heat the water.
2. The Related Art
Household water supply systems are common in modern society. Most of the household water supply systems include a water heater for the supply of warm water, which is essentially necessary for residents of cold zones in winter. Conventionally, the water heater heats water by burning gas or by electricity. Both consume additional energy in heating water.
In summer time, the room temperature may be as high as 25-35xc2x0 C., or ever higher. Water temperature that is suitable for most household applications is at most 34-40xc2x0 C., which is approximately 10 degrees higher than the room temperature. Water is often over-heated when the conventional water heater is employed to heat the water in summer time, which leads to a waste of energy. In addition, cold water must be mixed with the over-heated water to make the water temperature appropriate for immediate use. This causes waste of water, which in turn leads to a waste of energy.
Such a 10 degree difference can be readily and sufficiently compensated by a low power heater, which consumes power of 100-200 W. However, such a low power heater is not available in the market and thus it is desired to provide a water heating device that meets the requirement of environment protection and not excessively heating water.
An object of the present invention is to provide a water heating device without an additional and independent supply of energy for saving of energy.
Another object of the present invention is to provide a water heating device that requires no independent energy supply while capable to supply properly heated water without over-heating so as to be environment friendly.
To achieve the above objects, in accordance with the present invention, there is provided a water heating device comprising a hydroelectric power generation system, an electrical heater that is powered by the hydroelectric power generation system and a control unit for controlling the electrical heater. The water heating device is arranged on a pipeline connecting a water supply at a high location and a water faucet at a low location below the water supply. Water flowing from the water supply to the faucet drives a turbine of the hydroelectric power generation system, which in turn drives a generator via a transmission shaft. The generator is electrically connected to the control unit and the electrical heater by wires for supply of electricity to the electrical heater, which heats the water flowing through the pipeline. Thus, without additional and independent external power supply, the water heating device of the present invention properly heats the water for supply properly heated warm water to the faucet.